Search Results for: Brooms without handles
requires + dimensions. roughly, the whitney trick allows one to "unknot" knotted spheres – more precisely, remove self-intersections of immersions; it does this via a homotopy of a disk – the disk has dimensions, and the homotopy adds more – and thus in codimension greater than , this can be done without
loosely, ⁄ is enough, hence total dimension is enough), the whitney trick works. the key consequence of this is smale's h-cobordism theorem , which works in dimension and above, and forms the basis for surgery theory. a modification of the whitney trick can work in dimensions, and is called casson handles...
https://en.wikipedia.org/wiki/Geometric_topology